or tuna cans is a measure of the output of the system (in/hr). Repeat this procedure in each sprinkler zone, particularly if different types of sprinklers are used on different zones.
ADJUST SPRINKLER HEADS AS NEEDED. Improper adjustment of sprinkler heads not only wastes water but also may damage buildings or cause accidents if the water is allowed to spray onto buildings, public streets or sidewalks. Carefully adjust the radius and arc of part-circle sprinklers to prevent undesirable over-spray. Check the system several times during the year to ensure proper adjustment.
OPERATE SPRINKLERS BETWEEN 4 P.M. AND 10 A.M. Time of application affects water-use efficiency. The best time to irrigate with sprinklers is between 4 p.m. and 10 a.m. since the least amounts of sunlight and evaporation occur during these hours. GUIDELINES FOR IRRIGATING THE LANDSCAPE
CHECK THE APPLICATION RATE OF YOUR SPRINKLER SYSTEM. Application rate is the rate at which a sprinkler system applies water to the soil
AN AUTOMATIC CONTROLLER CAN HELP TO SAVE WATER. An automatic controller attached to the
surface, measured in inches per hours (in/hr). If
irrigation system turns the system on and off and
application rates exceed the absorption capacity of
controls the water flow through the various zones
the soil, then runoff occurs. Problems with runoff are
according to a pre-set time clock. It allows you to set
more likely to occur in clay soils that have a low
the length of time each zone operates as well as the
intake capacity.
days of the week and time of day the system operates.
Rotary sprinklers usually have application rates of
However, an automatic controller does not relieve
0.25 to 0.50 inches per hour and rarely cause runoff.
you of the need to closely monitor its operation.
Spray heads, on the other hand, typically have
Controllers should be re-programmed frequently
application rates between 1 and 2 inches per hour and
during the growing season because water needs
may cause runoff on heavy soils, especially where
change from week to week.
slopes are greater than 10 percent. If runoff occurs,
A rainfall sensor or rain switch attached to the
turn the system off for an hour or two to let the water
controller detects rainfall and prevents the irrigation
soak in, and then apply the remainder of the water.
system from operating if
Determine the application rate of a sprinkler
significant rainfall has occurred.
system by placing three or four rain gauges or empty
Another type of sensor measures
tuna cans at random on an irrigated area for a
soil moisture and overrides the
predetermined length of time (usually one hour). By
system when soil moisture is
knowing the application rates of your sprinkler
adequate. Sensors are
system, you will know how long to operate the system
especially useful if the system
to apply a given amount of water and will avoid
cannot be monitored and
wasting water. Average water level within the gauges
adjusted regularly.
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